Ingot and process of forming same



` nnhvmflqo. l PATENTED ,um 12, 1904.

l jH.w.LAsH. 4

f INGOT AND PROCESS 0F FORMING THE sAME. APPLICATION FILED 0UT.18, 189B. RENEWED 00T. 5. 1903.

2 SHE TS-SHEBT 2.

lio 'MODEL w/r/vEssEs AUNITEDK STATES Patented January 12, 1904.

PATENT OFFICE. g

-I HORACE W. LASH, OF MINNEAPOLIS, MINNESOTA.

|,NGOT AND PROCESS o|r FonMlNG SAME.

SPECIFICATION forming part of Letters Patent No. 749,490, dated January 12, 1904. Application filed October 18, 1898. `Renewed October 5, 1903. Serial No. 175,895. (No model.)

To all whom it may concern): 1

Be it known that I, HORACE W. LAsH, of the citykof Minneapolis, county of Hennepin, State of Minnesota, have invented certain new and usefulImprovements in the Art or Process of Forming Metal Ingots, of which the followh ing is a specification.

My inventlon relates Ato a novel process of forming or producing steel ingots wherefrom various articles may be manufactured by the usual forging, pressing, or rolling methods. At present steel ingots are formed or cast in molds, and owing to the costof molds and the expense of handling the same the practice has been to make the molds and ingots as large as possible to be handled with prot, with the result that the ingots produced are large and l unwieldy and require heavy and expensive machinery for cogging or reducing the ingots to sizes suitable for rolling into nished material. By employing large molds and heavy machinery it has been possible to produce steel in large quantities at a cost so small as to prohibit competition by small plants using small molds and light machinery. It is generally acknowledged that small steel ingots cannot be produced in competition with large ingots, for the reason that the cost of producingV a tonnage of small ingotsis much greater than that of "producing the same tonnage of large ing0t5- This is because of the excessive cost of small ingot-molds, the short life thereof, the extra labor required for placing the molds in ratio to the product and vfor'reinoving the ingots from the molds, the. excessive scrap that 1s produced in handling small ingots, and because it is almost impossible to `cast the entire a contents of alarge converter into small ingots,

owing to the rapid cooling of the molten steel after it is taken f rom the converter.

The object of this invention is to enable the production of steel ingots of comparatively small weight and cross-sect1on at a lowcost,

andthe particular object is to dispense with the use of molds entirely in the mauufacture y of ingots, and thereby greatly reduce the Icost 4 of casting or forming the ingots.

Another obJectof my Invention is to produce steel ingots thatshall be perfectly unlform in compositiom solidty, and weight throughout and, further, to enable the manufacture of hollow and tapered ingots without molds. l

Another object of my invention is to enable the cheap production of compound steel ingots direct from molten steel and in general theV production of ingots that'shall be free fromprovement in the art of forming steel ingotsl that consists in preparing a mass of molten Ametal, inserting a piece of cold metal into said mass, and thereby causing said molten steel to form or settle upon the exterior of said piece, thereby forming an ingot, and withdrawing such ingot 'from the molten mass prior to the general solidification of said mass.

The invention will be more readily understood by reference to the accompanying drawings, forming part of this specification, and in which- "Figure 1 illustrates my process of forming or growing metal ingots. Fig. 2 is a plan View of Fig. 1. Fig. 3 illustrates a fractured round ingot. of a tapered ingot which is also hollow. Fig. 5 is a cross-section thereof. Fig. 6 illustrates a continuous process of forming ingots, and

Fig. 7 illustrates a fractured compound grown ingot.

My process of forming ingots from and in a massof molten steel comprises the following steps: first, starting with the liquid metal already converted into steel and ready for casting and permitting the same to cool to within a few degrees above the melting-point either in the furnace or in a suitable receptacle wherein the steel is placed while in the liquid condition; second, while the mass is still mol- Fig. 4 is a longitudinal section l or crystallization, accretion, or coalescence is set. up within the mass, forming a solid body, unlt, or ingot which'may be withdrawn from the molten mass at will; This process of growth, which is a logical deduction from the tendency, to local accretive coalescent action or solidiiication in molten steel, is dependent largely for utility upon the temperature of the mass, and particularly upon the means employed to excite such local action or growth within the'molten mass. A

For starting the crystallization or formation of an ingot in the molten steel I prefer to use a bar, rod, plate, or block of metal, preferably iron or steel. Such a bar iscooler than the molten steel, and when it is placed in the molten mass the surrounding metal will instantly begin to grow, coalesce, orsolidify upon the rod, thus forming the beginning of the ingot, which will continue to grow and increase in size as long as it is allowed to remain in the molten mass. A few minutes only are required to thus create, form, or grow an ingotI several inches in diameter upon a small rod as a base or to form an ingot of uniform solidity and of -any desired thickness from or upon a relatively small plate or piece of metal.

In all cases theresultant ingot will possess substantially the same shape as the original bar or plate or fmoldfpieces, as it may be termed. Ingots lof irregular dimensions may be readily formed by varying the period of immersion of different parts.

I apply the name grown ingot to the product of my process as best describing its manufacture and its nature. This ingot possesses several important qualities not hitherto obtained in steel ingots-to wit, the quality of perfect consistency, uniformity, and density throughout-#the ingot being absolutely without blow-holes or air-cells, a naturally-finished unchilled surface, and uniformity of composition in all its parts. In yall ingots that are cast in molds there is found a center or core of chemically-imperfect metal, the same being an alloy of iron and the various impurities contained` inthe moltenmass and whichthrough;

. the natural process of segregation are forced to the center from the outer parts of the ingot, which cool first. This hard, brittle, or rotten center is very objectionable in the ingot and in all articles made therefrom, as it-greatly reduces the theoretical strength of the mass or bar and for manyuses must be bored out,

as in Steamship-shafts,

In my process segregation takes place, but not within the ingot, the impurities instead being eliminated from the metal as it cools and left in the molten mass or upon the surface of the ingot.

. In Fig. 1 of the drawings I have shown a.

pot, ladle,'or.well in which the metal is pre- -pared or is poured after preparation in a suitable furnace. 2 2 represent rods of iron or other metal the ends of which are thrust down into the molten mass of steel.` These rods promote or excite solidification or accretion to the metal surrounding the same, and in a few minutes a solid, mass or ingot will coalesce or grow upon the rod, and when the mass is suiiciently large it is Withdrawn by means of the rod. The free end of the rod is then cut off, and the ingot is ready for the rolls or for any reducing process. The greater part of the-steel in ladle will be removed in growing a numberlof ingots therefrom, and the material which is left, which will contain all the impurities, will be replaced in the furnace for reconversion or to be added to raw material. For convenience the ladle is preferably arranged upon trunnions, so that the metalA that isl left after a number of ingots have been made maybe easily poured out. The original metal `od or molding-piece remains in the ingot, the surrounding metal being firmly contractedl and welded thereon. The center rod will show, as indicated in Fig. 3, when an ingot is fractured or broken, and

the surface surrounding the rod at the fracture will possess the granular or crystalline appearance common to cast-steel. Tubular ingots may be readily formed,as indicated in Fig. 4, ay tube 5 being substituted for a solid rod, as shown in the preceding figures. The lower end of the vtube is plugged to prevent the metal from flowing upward therein. In th1s manner hollow ingots tobe manufactured into hollow shafts, car-axles, &c., may be manufactured much more cheaply than under4 the old methods.

A taper casting is readily made by gradually raising the ingot after a suiiicient quantity of metal has accumulated or grown thereon to give the proper dimensions to the upper end of I*ingot should be drawn away from the furnace by a gang of live-rolls 11., arranged before the door thereof. At the end' of the live-rolls I prefer to place powerful shears 12 for cutting the ingot into lengths. n

The simple or compound ingot or plate (shown in Fig. 7 comprises the thin original plate 13, upon which the body 14 of theingot is formed by the processof growth.

Aside from the better quality of materiall produced by my invention the principal advantage lies inthe cheapness of the process,

I of molten steel, then inserting a piece of cold and bythe aid f ducing from .fifty terior of said piece and thus form an ingot and then withdrawing such ingot from the molten l mass prior to the general solidification of said` mass, substantially as descri.

i Patenti metal ingots that consists in placing a piece of of the invention a plant prowithdrawing the original piece, with the into one hundred tons of steel daily may manufacture small lingots and compound ingots as cheaply as if producing a much larger tonnage and may be operated at points where the market is not sufliciently large to warrant the investment in a large mill of a thousand or more tons capacity daily, as required for the cheap production of steel under old methods.

Having thus described my invention, I claim as new and desire to secure by Letters stantially as described. t

6. The improvement in the art of forming hollow steel ingots from molten steel that consists in inserting the end of a closedV metal tube into the mass of molten metal and thereby causing the molten metal to chill or form upon the exterior of said tube and form an ingot, substantially as described.

7. The method of shaping metallic articles, consisting in lowering a former into a metallic bath and lifting the same gradually therefrom; substantially as described.

8. A new article of manufacture, comprising the herein-described ingot, composed of a metal` corey or mold piece and an inclosing mass of ingot metal, formed by inserting said core or mold piece ina mass of molten metal, allowing a quantity ofthe metal to solidify on said. core and then withdrawing said core, with the 'resultant ingot formation thereon, before said mass, as a whole, solidifies, substantially as described. metal plate in molten steel or the like, allowing 9. The product of the herein-described proca large quantity thereof to solidify thereon fess, comprisingv the central metal bar or moldand then withdrawing said bar lor plate with piece and the ingot-body formed thereon, by the resultant ingot formation thereon before the insertion of said mold-piece in a mass of said mass as a whole solidiiies, substantially as molten metal andpermitting the molten metal described. Y to solidify on said core-piecenntil the resultl 3. -The improvement in the art offorming ant ingot reaches the desired dimensions, and steel ingots that consists in cooling molten then withdrawing the ingot from said mass steelyto a temperature below that o f converwhile the latter is still molten. sion, then exciting or creating a local solidi- 10. lThe herei described tapered ingot, cation or growth in the molten mass by the incomprising a core or mold piece, and the introduction of a bar or piece of metal, permitgot-body formed thereon by inserting said ting said solidification or growth to continue l core in a mass of molten metal and then graduntil an ingot of severall times the weight of ually withdrawing the same from sald mass, the original bar or piece of metal is formed the art of forming in preparing a mass 1. The improvement in metal-ingots that consists thereby causing the settle Y upon the exmetal into said mass, molten steel to form or bed.

2. The improvement in the art of forming suiiicient time being allowed for extensive soand then withdrawing said ingot from the lidication of the metal on said core, and the mass of steel before the mass as a whole solidiingot being wholly withdrawn from said mass fies, substantially as described. whijle the latter is still plastic, substantially as described. i

11. A steel ingot having a core and a nonmolded body portion coaleseed thereon, such body portion being uniformly dense, homogefneous, and centrally free from segregated impurities.

In testimony whereof I have hereunto set my hand, this 7th day of October, 1898 at Minneapolis, Minnesota.

HORACE W. LASH.

4. The improvement in the artv 'of forming ingots that consists in inserting a single piece of cold steel into a mass of molten steel and. thereby causing said molten steel to form or' settle wholly upon the exterior of said piece and thereby forming an ingot, substantially as described.

5. The improvement in the art of forming ingots from molten metal that consists in inserting one end of a cold piece of metal into a mass of molten metal, thereby chilling the molten metal upon the cold metal `and causing a large accretion and growth thereon and then In presence of C. G. HAwLnY, M. E. GooLEY.

got accretion, from-the molten metal, sub- IOO 

